5-35. BLOWER - MAINTENANCE INSTRUCTIONS (Continued).
OVERHAUL - INSPECTION
Wear eye protection when using compressed air.
a. Wash all of the blower parts in clean fu l oil and dry them with compressed air.
b. Examine the bearings for any indications of corrosion or pitting. Lubricate each bearing with light
engine oil; then, while holding the bearing inner race from turning, revolve the outer race slowly by
hand and check for rough spots.
The double-row ball bearings are pre-loaded and have no end play. A new double-row bearing will
seem to have considerable resistance to motion when revolved by hand.
d. Check the oil seal rings, carriers and collars for wear and scoring. If worn excessively, they must be
replaced. Inspection of the lip type oil seal is covered in item step 4n.
e. Inspect the blower rotor lobes, especially the sealing ribs, for burrs and scoring. Rotors must be
smooth for efficient operation of the blower. If the rotors are slightly scored or burred, they may be
cleaned up with emery cloth.
Examine the rotor shaft serrations for wear, burrs or peening. Also, inspect the bearing and oil seal
contact surfaces of the shafts forwear and scoring.
g. Inspect the inside surface of the blower housing for burrs and scoring. The inside surface must be
smooth for efficient operation of the blower. If the inside surface of the housing is slightly scored or
burred, it may be cleaned up with emery cloth.
h. Check the finished ends of the blower housing for flatness and burrs. The end plates must set flat
against the blower housing.
The finished inside face of each end plate must be smooth and flat. If the finished face is sghtly
scored or burred, it may be cleaned up with emery cloth.